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14.1 Urban and Environmental Framework
14.1.1 General Remarks on Prague
Prague is the capital of the Czech Republic. As the largest city in the country by its
area (496 km
2 ) and by population (1.2 million inhabitans) faces the same environmental challenges, as the other large cities in the world. The city strives for the
substantial reduction of the environmental burden as to become clean, healthy, and
harmonic place for living. Prague is situated on the banks of the Vltava river and its
tributaries. The complicated morphology creates limitation for a good ventilation of
the area. The lowest point is in 149 m and the surrounding hills at the southwestern
part of Prague are almost 400 m above sea level.
14.1.2 Prague Urban Heat Island Analysis
Prague and especially its city centre belongs to the warmest regions of the Czech
Republic with annual average air temperature around 10 °C in the city centre (see
Fig. 14.1). This is partly caused by the urban heat island (UHI) of Prague.
The intensity of UHI is about 1.6 °C when we use the average daily temperatures. The highest intensity occurs during June, while the lowest intensity in
September. It has to be noted, that the UHI intensity of Prague is considerably
higher when looking at minimum temperatures (annual average is approximately
3 °C) but smaller for maximum temperatures (annual average approx. 1 °C). The
intensity of Prague’s UHI has increased during the last 50 years. This increasing is
caused due to the city enlargement and transport intensification.
The magnitude of this intensification is 0.15 °C/10 years for minimum temperatures, 0.07 °C/10 years for average daily temperatures and 0.02 °C/10 years for
maximum temperatures. This intensification of UHI is documented on Fig. 14.2
where differences of daily air minimum temperatures between period 2001–2010
and 1961–1970 are demonstrated. While the temperature in the whole Prague area
increases (due to the climate change in the Central Europe), the largest increment of
the temperature can be seen in city centre, close to the Vltava river, in the densely
built up part of the city.
Another point of view of the intensity of UHI can be obtained by using physiological equivalent temperature PET (Matzarakis et al. 2010). This temperature
describes the temperature really felt by the human being standing outside and
includes not only influence of air temperature and wind, but also humidity and radiation including the radiation coming from buildings in the streets. The average
annual and daily course of PET for the Praha–Karlov stations is given in Fig. 14.3.
It can be seen, that the highest values occur during summer months, July and the
first half of August.
M. Žák et al.
14.1 Urban and Environmental Framework
14.1.1 General Remarks on Prague
Prague is the capital of the Czech Republic. As the largest city in the country by its
area (496 km
2 ) and by population (1.2 million inhabitans) faces the same environmental challenges, as the other large cities in the world. The city strives for the
substantial reduction of the environmental burden as to become clean, healthy, and
harmonic place for living. Prague is situated on the banks of the Vltava river and its
tributaries. The complicated morphology creates limitation for a good ventilation of
the area. The lowest point is in 149 m and the surrounding hills at the southwestern
part of Prague are almost 400 m above sea level.
14.1.2 Prague Urban Heat Island Analysis
Prague and especially its city centre belongs to the warmest regions of the Czech
Republic with annual average air temperature around 10 °C in the city centre (see
Fig. 14.1). This is partly caused by the urban heat island (UHI) of Prague.
The intensity of UHI is about 1.6 °C when we use the average daily temperatures. The highest intensity occurs during June, while the lowest intensity in
September. It has to be noted, that the UHI intensity of Prague is considerably
higher when looking at minimum temperatures (annual average is approximately
3 °C) but smaller for maximum temperatures (annual average approx. 1 °C). The
intensity of Prague’s UHI has increased during the last 50 years. This increasing is
caused due to the city enlargement and transport intensification.
The magnitude of this intensification is 0.15 °C/10 years for minimum temperatures, 0.07 °C/10 years for average daily temperatures and 0.02 °C/10 years for
maximum temperatures. This intensification of UHI is documented on Fig. 14.2
where differences of daily air minimum temperatures between period 2001–2010
and 1961–1970 are demonstrated. While the temperature in the whole Prague area
increases (due to the climate change in the Central Europe), the largest increment of
the temperature can be seen in city centre, close to the Vltava river, in the densely
built up part of the city.
Another point of view of the intensity of UHI can be obtained by using physiological equivalent temperature PET (Matzarakis et al. 2010). This temperature
describes the temperature really felt by the human being standing outside and
includes not only influence of air temperature and wind, but also humidity and radiation including the radiation coming from buildings in the streets. The average
annual and daily course of PET for the Praha–Karlov stations is given in Fig. 14.3.
It can be seen, that the highest values occur during summer months, July and the
first half of August.
M. Žák et al.